Codes and Frequencies
PHLEBYRC indicates whether the person had chronic phlebitis or thrombophlebitis in the past year. This variable is created with supplemental programming by the IPUMS NHIS staff from the pre-1997 condition records. For general information about IHIS variables (such as PHLEBYRC) created from the pre-1997 condition records, see the User Note on Condition Records and Condition Variables.
Defining Phlebitis/Thrombophlebitis Records and Identifying Persons with Phlebitis/Thrombophlebitis
For all available years, persons who were asked a direct question about phlebitis/thrombophlebitis and who have a chronic phlebitis/thrombophlebitis condition record are given a "Yes" code for PHLEBYRC. Persons who were asked a direct question about phlebitis/thrombophlebitis but do not have a chronic phlebitis/thrombophlebitis record are given a code of "No." Persons who were not asked a direct question about phlebitis/thrombophlebitis, or for whom it is unknown whether they were asked such a question, are given a code of "NIU" (not in universe), regardless of whether they have a chronic phlebitis/thrombophlebitis record.
For 1972 and 1978-1981, phlebitis/thrombophlebitis records were defined as those condition records with a code of "139" ("Phlebitis and thrombophlebitis, [not elsewhere classified]") in the variable DIAGR1 in the variable DCICDCOD in the original NHIS public use files. This condition code value comes from NCHS's Diagnostic Recode #1: Diseases, Injuries, and Impairments. Additionally, to be considered "chronic," phlebitis/thrombophlebitis condition records must have a code of "1" ("Chronic") in the variable CACODE in the original NHIS public use files.
For 1982-1996, chronic phlebitis/thrombophlebitis records were defined as those condition records with a code of "512" ("Phlebitis, thrombophlebitis") in the variable C1CONDRC in the original NHIS public use files. This condition code value comes from NCHS's Diagnostic Recode C: Chronic Conditions and Impairments.
As with all of the person-level condition variables created by IHIS from condition records prior to 1997, the universe for PHLEBYRC is substantially different for 1978 forward than it is for years prior to 1978. Beginning in 1978, only persons living in 1/6 of households, rather than all persons, were asked a direct question about having phlebitis or thrombophlebitis in the past year. This change requires that different weight variables be used depending on which years of data are analyzed. See the "Weights" tab for details.
Additionally, there is a change in the way "Yes" responses are coded over time. See the User Note on Condition Records and Condition Variables for details about the composite coding scheme employed by IHIS.
- 1972: All persons.
- 1978-1996: Persons living in 1/6 of households (who received Condition List 5).
- 1972, 1978-1996